1. Binary systems: from 0.2 arcsec to 2 deg José Antonio Caballero
Centro de Astrobiología (CSIC-INTA), Madrid
Double stars observers 2010

2. Formation, evolution and multiplicity of brown dwarfs and giant exoplanets
Planets in close orbits: search for transits ( photometric variability) Planets in wide orbits: deep wide imaging
No planets with CAIN-II/1.5m TCS… An example, a stable, “single” brown dwarf: Kelu 1
Caballero 2006, PhD

3. Substellar objects De fuscis pusillis astris et giganteis exoplanetis
2H burning
1H burning
Mass
(Msol [MJup])
(Zsol)
star
yes
>0.075
[> 72]
Sub-stellar object
Brown dwarf no
[72-14]
Planet
<0.013
[< 14]
Caballero 2006, PhD

4. Search for very low-mass objects surrounding nearby young stars Direct imaging with near-infrared adaptive optics systems at 4 m-class telescopes:
Naomi+Ingrid / 4.2 m WHT
Alfa+Omega-Cass / 3.5 m Calar Alto
AdOpt-at-TNG / 3.6 m Telescopio Nazionale Galileo
And coronography with:
NICMOS / Hubble Space Telescope
Caballero 2006, PhD

5. Search for very low-mass objects surrounding nearby young stars Complement: wide-field search with CAIN-II / TCS and other instruments Able to detect all brown dwarfs at s > 50 AU and all planets with M > Msol at s > 100 AU...
Example: G 196-3A and B, a young star in the Local Association with an L-type companion of… Msol
Caballero 2006, PhD

6. Caballero 2006, PhD
HD AB: from 7 x 7 arcmin2 to 3 x 3 arcsec2

7. Search for very low-mass objects surrounding nearby young stars 51 systems with features of youth (lithium, chromospheric activity, X-ray emission, membership in moving groups): - 44 with ages  600 Ma - 32 with ages  100 Ma * 3-4 new stellar companions * Upper limits on the frequency of companions * BUT... AB Dor C HD AC HN Peg B
Caballero 2006, PhD

8. Search for very low-mass objects surrounding nearby young stars 51 systems with features of youth (lithium, chromospheric activity, X-ray emission, membership in moving groups): - 44 with ages  600 Ma - 32 with ages  100 Ma * 3-4 new stellar companions * Upper limits on the frequency of companions * BUT... AB Dor C HD AC HN Peg B
Caballero 2006, PhD

9. Caballero+ “De Mayrit al cielo”: Orionis cluster
( ~ 3 Ma, d ~ 385 pc)
The most complete initial mass function (from 18 to Msol)
Brown dwarfs (with discs, X-ray emission, Ha emission…) and “isolated” planetary-mass objects
Caballero+

10. Caballero 2009, CoolStars15 “De Mayrit al cielo”: Orionis cluster
( ~ 3 Ma, d ~ 385 pc)
Very wide binaries + Statistical approach
3 resolved systems with probabilities of alignement by chance of 1% (2 are triple)
Separations: arcsec ( AU)
And…
Caballero 2009, CoolStars15

11. Caballero et al. 2006, A&A “De Mayrit al cielo”: Orionis cluster
( ~ 3 Ma, d ~ 385 pc)
“B”: S Ori 68: L5.0, ~5 MJup, Ha
“A”: [SE2004] 70: M6.0, ~45 MJup, low-gravity, X-ray flare, Ha, radial velocity, Li I
= 4.6 arcsec  s =1700 AU
The widest “planetary” system?
Caballero et al. 2006, A&A

12. Caballero+ “De Mayrit al cielo”: Orionis cluster
( ~ 3 Ma, d ~ 385 pc)
Important because:
it illuminates the Horsehead Nebula
X-ray emitter population
discs at 3 Ma
a helium-rich, magnetically-active B2Vp star
Herbig-Haro objects
accretion rates and frequency…
Caballero+

13. s Ori (Uranometria: Bayer 1603) 48 Ori (Flamsteed’s catalogue: Flamsteed 1712) BD (Bonner Durchmusterung des sudlichen Himmels: Schonfeld 1886) HD (Henry Draper catalogue: Cannon & Pickering 1925)
Caballero 2006, PhD

14.  Ori E (Tabula Nova Stellarum Duplicium: Mayer 1779)  Ori C, D (Struve et al. 1876) s Ori B (Burnham 1892)
Caballero 2007, AN

15. A near-IR counterpart of a mid-IR source: s Ori IRS1, an evaporating proplyd?
Also detected in X-rays (Caballero et al. 2010, A&A) AU
Caballero 2005, AN

16. On-going high-resolution (lucky) imaging (with FastCam/1.5 m TCS)
A*: O9.5V, 18 Msol
B: B0.5V, 12 Msol
C: A2.0V, 2.7 Msol
D: B2.0V, 6.8 Msol
E: B2.0Vp, 7.4 Msol
s Ori B
s Ori IRS1
s Ori A
Caballero in prep.

17. Angular separation of r ~ 0.26 arcsec (with FastCam/2.5 m NOT)
Caballero in prep.

18. Angular separation of r ~ 0.26 arcsec (with FastCam/2.5 m NOT)
And NaCo/8.4 m VLT resolves s Ori IRS1!
Un-published

19. s Orionis: The most massive “binary” with an astrometric orbit (Mason et al.)
Caballero in prep.

20. Orionis: The most massive “binary” with an astrometric orbit (Mason et al.)
New fit: a =  arcsec e =  i =  1.0 deg P =  0.5 a
Caballero in prep.

21. Simón-Díaz & Caballero in prep.
On-going high-resolution spectroscopy
(P’~143 d; Aa: O9.5V, 18 Msol, Ab: B0V, 15 Msol)
TAa = 34 kK, vsini = 110km/s
TAb = 32 kK, vsini = 30km/s
TB = 31 kK, vsini = 60km/s
Up to = 45 Msol!
Simón-Díaz & Caballero in prep.

22. Caballero 2008, A&A

23. The mass function down to the planetary domain in the s Orionis cluster  Derivation of the mass function from 0.11 to Msol, with index a = (DN/DM  M-a; Salpeter: a = 2.35).  Frequency of s Orionis brown dwarfs with discs is 47 ± 9 %
Caballero et al. 2007, A&A

24. The mass function down to the planetary domain in the s Orionis cluster  Derivation of the mass function from 0.11 to Msol, with index a = (DN/DM  M-a; Salpeter: a = 2.35).  Frequency of s Orionis brown dwarfs with discs is 47 ± 9 %
Caballero et al. 2007, A&A

25. Caballero 2007a, A&A

26. Caballero 2007a, A&A Koenigstuhl 1AB: a serendipitous discovery…
A: LEHPM 494 [?]
B: DENIS J [M9.5V]
r ~ 1.3 arcmin
B UK Schmidt
R ESO
IJK DENIS
R UK Schmidt
I UK Schmidt
JHKs 2MASS
[3.8:8.0] Spitzer
Caballero 2007a, A&A

27. Koenigstuhl 1AB: the (second) widest ultracool binary: a challenge for very low-mass formation ejection scenarios!
 = ± 0.07 arcsec
d = 23 ± 2 pc
s = 1800 ± 170 AU
MA = ± Msol
MB = ± Msol
Highlight of the week in A&A. Almost cover page!
Caballero 2007a, A&A

28. Koenigstuhl 2 AB: A new very low-mass star in a wide binary (the third widest system with MA + MB < 0.4 Msol)
Primary: LP
(Luyten 1979)
Secondary: 2M (M8.0V; Cruz et al. 2003)
s = 450 ± 40 AU
MA = 0.26 ± 0.04 Msol
MB = ± Msol
Caballero 2007b, ApJ

29. Koenigstuhl 3 ABC: the widest system containing an L dwarf component
Primary: HD
(F8.0V; Hipparcos)
Secondary: 2M AB (M8.0V+L3.0V; Gizis et al. 2000, 2003)
r = ± arcmin
s = ± 300 AU
MA = 1.02 ± 0.07 Msol
MBC = Msol
Caballero 2007b, ApJ

30. Caballero, Miret et al. in prep
A Virtual Observatory search for companions to Luyten stars
20 physical systems with both star components in Hipparcos
29 physical systems with only one star component in Hipparcos
19 physical systems with no components in Hipparcos
Half a dozen new serendipitously-discovered physical systems
Caballero, Miret et al.
in prep

31. Caballero et al. 2010, A&A G 125-15 AB + G 125-14 = WDS 19312+3607
(see paper in folder)
Caballero et al. 2010, A&A

32. Caballero et al. 2010, A&A

33. Reaching the boundary between stellar kinematic groups and very wide binaries. I
WDS stars with the widest angular separations (r > 999 arcsec): N=30
Visual or unidentified doubles: N=23
Physical double candidates: N=7 (including a Centauri A, B and C)
Caballero 2009, A&A

34. Reaching the boundary between stellar kinematic groups and very wide binaries. I
Six stars with s > 0.1 pc (previously assumedupper limit to the distribution of wide binary semimajor axes)
Four stars with s > 0.2 pc
Comparison of gravitational binding energies (U=-GMAMB/r)
Caballero 2009, A&A

35. Caballero 2009, A&A

36. The widest binary! Caballero 2010, A&A
Reaching the boundary between stellar kinematic groups and very wide binaries. II
The widest binary!
Caballero 2010, A&A

37. Caballero 2007a, A&A

38. Caballero & ??? Future: Luyten stars (& Miret et al.)
nearby young stars (& Alonso-Floriano, Montes)
ultracool dwarfs (& Montes)
and much, much more…
Caballero
& ???